You're about to board a huge, sealed metal cylinder, sit down, eat a meal and watch a movie while whizzing over the ground at 900km/h and that in itself is astonishingly weird, yet it's something we do without thinking twice. Here are 10 more weird things to ponder when you take to the skies.

1. What happens if an engine dies during flight?

No problem. Modern aircraft can continue to fly safely with an engine out, even if it's a two- engine plane. If all engines die the dynamics are not so great. That's what happened in 1982 to a British Airways Boeing 747 when it flew through a cloud of volcanic ash over Indonesia and all four engines progressively snuffed out. In a masterpiece of pilotspeak right stuff Captain Eric Moody announced "We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress." Happily for all the pilot was able to restart the engines when the aircraft, in glide mode, exited the ash cloud, but after some passengers had already written farewell messages.

2. Why does this wine taste strange?

Dry air, cabin pressure, they dry up your sinuses and numb your taste buds. The nobs in the pointy end might be socking back Krug but sorry, it doesn't taste the same at 10,000 metres. More acidic, big tannin wines suffer at altitude, which is why most airlines tend to prefer aromatic, fruity wines. By the way, while an airline might enlist big-name wine buffs to choose their wines they don't taste them at altitude. Big mistake.

3. Where's my life vest?

Under the seat usually, but you might want to check. People souvenir these handsome fashion items. Not there? Alert the flight attendants. While the chance you'll ever need it is infinitesimally small, you wouldn't want to be the one treading water when all the other passengers are bobbing around in their pretty yellow life jackets whistling in harmony.

4. Oxygen masks just flopped down, how long have I got?

If the aircraft is at cruise altitude and you're breathing normally, about 15 seconds before you start to feel short of breath. Another 15 seconds and you could pass out. That's the reason the safety briefing advises you to put yours on before helping anyone else. The oxygen system will keep you pumping for about 15 minutes, which is plenty of time for the pilot to fly the aircraft to a lower altitude.

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5. Can an aircraft door be opened inflight?

Aircraft doors are designed to open inward, then they usually rotate before they open out. Since the pressure inside the cabin is higher than outside, the door is being pushed outward even at relatively low altitudes, creating a seal. You'd need to overcome that seal to move the door inward, and that's more than any human or even half a dozen superstrong humans could do. You might heave it open with a tractor but that's hard to get on board.

6. Can lavatories be unlocked from the outside?

If a passenger falls unconscious or suffers an injury or if a child gets trapped inside, the flight attendants need to open the door, and they can. The metal plate with the word "Lavatory" is hinged. Lift it up and behind is a small lever that springs the door. Don't be tempted, even if you've been queuing 15 minutes.

7. Why is there an ashtray in the toilet?

That one right next to the "No Smoking" sign? Because if some desperado lights up it's better that they stub out in an ashtray rather than tossing their burning butt into the waste paper bin, where havoc might ensue. Back in 1973 a Brazilian Boeing 707 crash landed in France when the cabin filled with smoke, believed to have been caused by a cigarette burning in a toilet waste paper bin, with 123 deaths.

8. Do pilots get special meals?

Some do, but mostly it's a selection from the inflight menus, first or business class. At the insistence of their airline, what they usually get is different meals. If one becomes incapacitated due to contaminated food, the other can do the flying (and avoid a Flying High situation).

9. Is that blanket clean?

If it's sealed in a plastic bag you're in luck but if not then it's most likely been on someone else's lap. Fresh, clean blankets usually come on board on the first flight of the day when the aircraft is stationed in a provisioning airport. In between flights blankets are refolded and stacked in the overhead lockers. Maybe keep the blanket for legs only, or BYO jumper. Same goes for the pillow, under your back ok, maybe not your head.

10. Window shades up – why?

Since most aircraft accidents happen on take-off or landing it's important for passengers as well as crew to see what's happening outside. In at least one case the pilots didn't realise that an engine was burning on a taxiing aircraft until alerted by passengers.